Nebojsa Tower

A recently renovated canon tower in Kalemegdan built around 1460. Originally built to defend the city against the Turks, but it was actually turned into a Turkish prison later.

Worth visiting for its interesting exhibitions on history. You can learn more about how the tower worked as a part of the city defense system and as a prison. There's also an exhibition about the Greek revolutionary Rigas Velestinlis who was held prisoner here.